Pollux 2 Inertial Navigation System
Micro-miniature inertial navigation system for Unmanned Aerial and Land Applications

The capabilities of Unmanned Aerial Vehicles (UAV) or Drones are steadily expanding to cover a wide range of applications. UAVs are being used extensively for surveying and mapping, aerial photography, payload carrying, asset inspection, target testing and aerial surveillance applications. Their use for military purposes has gained tremendous attention due to the effectiveness in operating these micro- and mini-drones with stealth in strategically important and environmentally challenging conditions. A UAV is typically equipped with an ‘Autopilot’ to perform the mission goals as per the planned objectives. For controlling, stabilizing and guiding a UAV, the ‘Autopilot’ fetches motion parameters from the Inertial Measurement Unit (IMU) or Inertial Navigation Systems (INS) and optionally from LiDAR sensors. These sensors largely contribute to the performance parameters of the ‘Autopilot’ operations. The commercially available UAVs/Drones in the market mostly use the Off-the-Shelf Autopilot Hardware to offer solutions. These consumer grade UAVs use IMUs which are very poor in performance. It is therefore preferred in professional autopilots to integrate external IMU and GPS or use INS instead of using a low-performance built-in IMUs onboard the commercial ‘Autopilot Hardware’.

Moreover, the position data from GPS generally comes at 5Hz or 10Hz update rates and when used as an independent sensor to integrate with ‘Autopilot Hardware’ is not satisfactory for high speed manoeuvres of most UAVs for control and guidance. Combining IMU and GPS data to get position, velocity and orientation (attitude and heading) parameters is a tricky problem is already solved by Inertial Navigation Systems (INS) but INSs are typically very expensive even for professional, industrial or military applications.

Aeron’s Pollux2 family’s model PLX2-NS10 GNSS aided Inertial Navigation System (INS-GPS) is specially designed for UAVs or Drones including Quadcopters or multi-copters, fixed-wing, and VTOL drones for control, stabilization and precise way-point guidance applications. It is a tactical class INS that offers uncompromised performance even in short term GPS outages like urban areas, tree canopies, and hilly regions. In Pollux NS10, you get complete tactical navigation solution in a very small SWAP (Size, Weight and Power) and in an affordable cost that makes scalable UAV applications possible. It is equipped with low bias instability gyroscopes, accelerometers, low noise magnetometer, static barometer sensor and a multi-constellation GNSS receiver.

Aeron’s proprietary ‘Multi-mode Kalman Filter Based Sensor-Fusion algorithm’ delivers accurate estimates of navigation and control data comprising position, velocities, Euler angles, rates and accelerations. The navigation data is available at update rates of  50Hz, and control data (acceleration and rates) at 200Hz over standard RS232, RS422 and USB interfaces and protocols to handle the high dynamic requirements and integrity aspects.  Unlike most MEMS based INS systems in the market which offer higher update rates however at the cost of not performing proper filtering and estimation, Aeron’s Pollux 2 runs sensor fusion algorithm with all the necessary state estimates to deliver control grade navigation data.

The special case of ‘Target Drone’ requirements demands the rugged INS-GPS to sustain the high ‘g’ conditions during the initial launch phase. The system ruggedization is required to handle these types of performance-critical requirements. The PLX2-NS10 INS-GPS is ruggedized to meet such requirements. 

The precise position information is also required for the LiDAR-based mapping application for georeferencing. The Pollux2 variant, PLX2-NS20 offers identical inertial performance like the PLX2-NS10 model with an improved position accuracy of 2cm in RTK configuration.